This invention relates to a shock absorber of the energy absorbing type, for example, as provided between the bumper and chassis of a motor vehicle, and including a slidable member such as a piston or a friction member fitted in an outer cylinder for absorbing a shock by means of hydraulic fluid or frictional resistance, and more particularly, to a retainer for retaining the slidable member in the outer cylinder.
According to prior art shock absorbers, for example as shown in German Offenlegungsschrift No. 2,342,033, a slidable member such as a piston slidably inserted in an outer cylinder is retained in the outer cylinder by means of an arcuate retaining ring which engages with an annular groove formed in the inner peripheral surface of the outer cylinder.
However, such a retaining means is complex in construction, and the manufacture of the annular groove and the retaining ring results in the expenditure of substantial time and effort. Furthermore, the annular groove sometimes damages an oil seal fitted on the piston during the assembling operation.